1. Field of the Invention
This invention relates to a respiration exercising device and, in particular, to a device for enhancing inspiration for improvement of pulmonary performance. More specifically, this invention relates to a respiration exercising device that, in a first mode of operation, operates as a volume measuring device, and, in a subsequent mode of operation, operates as a flow-rate dependent device.
2. Description of the Prior Art
One of the main causes for slow recovery of patients following pulmonary operations has been inadequate oxygen exchange in the lungs resulting from shallow breathing accompanying the use of general anesthesia. This condition can lead to partial or complete collapse of the lungs and to pneumonia.
Various methods have been proposed for preventing or minimizing such pulmonary complications, including instructions to the patients to breath deeply, coughing exercises, and the use of blow bottles of the type described in U.S. Pat. No. 3,811,671. In some cases, such methods of blowing exercise have not been successful because alveoli have not been adequately expanded. Accordingly, numerous devices employing positive pressure breathing have been introduced to stimulate a patient to improve his or her inspiratory capacity.
Previously known breath exerciser devices and inspirators are described in British Pat. Nos. 8,662 and 685,815. Also, such devices are described in U.S. Pat. Nos. 471,389, 793,177, 3,635,214, 3,695,608, 3,754,546, 3,822,699, 3,908,987, 3,936,048, 3,811,671, 4,060,074, and 4,025,070.
With the exception of the blow bottle-type exercising device, the previously known devices have not provided any indication of the volumetric capacity of the patient. Since the interior dimensions of previously known devices have been variable, air leakage around the blocking devices used in the devices has limited their usefulness to measure volume.